1. Field of the Invention
The present invention relates generally to fifth wheel assemblies for coupling semi-trailers to tractors. More particularly the invention relates to a fifth wheel mounting pin. Still more particularly, the invention relates to a riser adaptation on a fifth wheel to simplify the extraction of mounting pins.
2. Description of the Related Art
Large highway freight trailers are usually coupled to an associated tractor by means of a fifth wheel assembly. The fifth wheel assembly, located about the longitudinal axis of the tractor frame between the rear drive wheels and the front steering system, often contains a mounting bracket and a hitch plate. The hitch plate is coupled to the mounting bracket by mounting pins on both sides of the fifth wheel assembly which are inserted from the exterior of the hitch plate assembly through the hitch plate and mounting bracket.
Mounting pins are retained in place by either bolting them to the side of the fifth wheel or by using a retaining pin or bolt. However, due to the tight fit of the mounting pin to the fifth wheel assembly, as well as corrosion, grime, and other factors, extraction of the mounting pin can be extremely difficult. A great amount of force must often be used to pry the mounting pin from the fifth wheel assembly. Furthermore, in certain types of fifth wheel assemblies, special tools are required to assist in the extraction of mounting pins.